Is ball of the foot roundhouse outdated with modern shoes?

J. Pickard

Brown Belt
Joined
Jun 8, 2020
Messages
403
Reaction score
394
You get more mass into the target from something that digs deep, rather than simply scrape on the outside, which is why a slap doesn't hurt you and why a soft beach boll thrown, no matter how heavy, won't hurt you, but a lighter rock will.
the rock vs ball thing is because of kinetic energy, more specifically the velocity part (and elasticity which is a whole other mess of math to add) , not mass. For ground and pound, the mass is the same, what you are changing is the compression force applied to the target not the mass. If you increase the mass of a beach ball enough it will, in fact, hurt you. You can also increase the velocity of a normal sized beach ball and hurt someone up to a point. This is basic physics that has been explained on this thread repeatedly. How are you not getting this?
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
the rock vs ball thing is because of kinetic energy, more specifically the velocity part (and elasticity which is a whole other mess of math to add) ,
No it isn't. Velocity can be exactly the same.. The beach boll won't hurt you even though it has more weight because it doesn't transfer that mass effectively. The rock however does by default.

It doesn't need to involve stone vs plastic material. It's the same thing if I tap you with a fast round kick compared to if I dig into you with a slower but more tensed round kick. The slow one will transfer more mass even though it's the exact same object hitting you in both instances. The second one is slower but more impactful
 

J. Pickard

Brown Belt
Joined
Jun 8, 2020
Messages
403
Reaction score
394
No it isn't. Velocity can be exactly the same.. The beach boll won't hurt you even though it has more weight because it doesn't transfer that mass effectively. The rock however does by default.

It doesn't need to involve stone vs plastic material. It's the same thing if I tap you with a fast round kick compared to if I dig into you with a slower but more tensed round kick. The slow one will transfer more mass even though it's the exact same object hitting you in both instances. The second one is slower but more impactful
FFS, this is not how physics works! You are so far beyond wrong it is causing me physical pain! If you make a beach ball out of a literal tonne of plastic it will crush you no matter what. If it is 600kg directly on top of you it will hurt you. if you accelerate a beach ball to a speed just before it shatters it will hurt you. Pain from an object hitting you, what we will call impact force is measured using Kinetic energy, momentum, and compression among other things because biophysics is complicated. In fact her, here is a link to a video showing how the mass andvelocity of a beach ball effects the force it delivers. What you described as a "tap" with a kick vs "diggin in" is literally the difference in KE and compression as I explained and both are a product of mass and VELOCITY!
I can't with you anymore.
 

Dirty Dog

MT Senior Moderator
Staff member
Lifetime Supporting Member
Joined
Sep 3, 2009
Messages
23,355
Reaction score
9,095
Location
Pueblo West, CO
At this point, a quote from Austrian Physicist Wolfgang Pauli seems appropriate.
"This isn't right. This isn't even wrong."
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
FFS, this is not how physics works! You are so far beyond wrong it is causing me physical pain! If
Velocity
the speed of something in a given direction.

That has nothing to do with the fact that my consistently slower punch that I don't let go off, is harder than the one I snap at the bag.
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
FFS, this is not how physics works! You are so far beyond wrong it is causing me physical pain! If you make a beach ball out of a literal tonne of plastic it will crush you no matter what. If it is 600kg directly on top of you it will hurt you. if you accelerate a beach ball to a speed just before it shatters it will hurt you. Pain from an object hitting you, what we will call impact force is measured using Kinetic energy, momentum, and compression among other things because biophysics is complicated. In fact her, here is a link to a video showing how the mass andvelocity of a beach ball effects the force it delivers. What you described as a "tap" with a kick vs "diggin in" is literally the difference in KE and compression as I explained and both are a product of mass and VELOCITY!
I can't with you anymore.
. I exaggerated about the volley boll. It will eventually do damage but it takes soo much . And that's due to the fact that penetration affects mass transfer into someone.
 
Last edited:
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
Sorry speed, not weight...it takes so much speed that it's silly.

But also weight...
 
Last edited:

dvcochran

Grandmaster
Joined
Nov 7, 2017
Messages
7,047
Reaction score
2,297
Location
Southeast U.S.
Velocity is delta x over delta t.

It has zero to do with your argument about the area of the striking member.
However, in the case of two members of the same mass traveling at the same velocity where one has a smaller area striking the same material, the penetration would be greater for the smaller member.

I suspect this is the argument you were trying to make but failing at poorly.

So, IF all things are equal, then yes, a correct ball of the foot kick will do more ‘damage’.
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
However, in the case of two members of the same mass traveling at the same velocity where one has a smaller area striking the same material, the penetration would be greater for the smaller member.

’.

No. Ball of the foot is skin ,instep is Bone. Again discounting the fact that Hardness of the material affect penetration...and penetration affects power.
 

andyjeffries

Senior Master
Joined
Sep 25, 2006
Messages
2,019
Reaction score
340
Location
Stevenage, Herts, UK
If I have to ask an instructor, get rid of the middle man, that is the book, and have the instructor speak sensible English. His point about beginning backward motion is both wrong and incomprehensible. His point about standing leg bent for side kick is Karate residuals and wrong in his own ITF.
This is always the case. The book is extra detail for those that understand it. No one is really intending to teach Taekwondo via book, the book is there as a help for those that can understand it.

I often have students say "shall I learn my next pattern from this book or YouTube" after testing, the answer is hell no!!! You learn from an instructor, books and videos are memory aids for most and details for those that can get them.

In this case the book potentially is badly worded (or at least not explained fully) so the best case is to have an instructor that does know (e.g. GM Weiss) explain how that was intended based on their experience at training with seniors.
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
This is always the case. The book is extra detail for those that understand it. No one is really intending to teach Taekwondo via book, the book is there as a help for those that can understand it.

I often have students say "shall I learn my next pattern from this book or YouTube" after testing, the answer is hell no!!! You learn from an instructor, books and videos are memory aids for most and details for those that can get them.

In this case the book potentially is badly worded (or at least not explained fully) so the best case is to have an instructor that does know (e.g. GM Weiss) explain how that was intended based on their experience at training with seniors.

It's not just that. He writes "toes of the stationary foot should point 45 degrees outward in the turning kick" , yet he uses a picture with an 180 degree pivot.

If you can't distinguish a 180 degree pivot from a 45 degree, you have no business writing a TKD textbook.

I wouldn't trust Choi about anything. He's the Donald Trump of TaeKwonDo. He just put his name on it as founder.
 

Attachments

  • Screenshot_20211004-131131.png
    Screenshot_20211004-131131.png
    780.7 KB · Views: 67
Last edited:

Dirty Dog

MT Senior Moderator
Staff member
Lifetime Supporting Member
Joined
Sep 3, 2009
Messages
23,355
Reaction score
9,095
Location
Pueblo West, CO
I wouldn't trust Choi about anything. He's the Donald Trump of TaeKwonDo. He just put his name on it as founder.
So why do you train in a system founded by someone you hold in such contempt? How does your instructor feel about your attitude?
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
So why do you train in a system founded by someone you hold in such contempt? How does your instructor feel about your attitude?

I don't hold innocent ignorance in contempt. I highlighted the fact that his 87 textbook is riddled with either inaccuracies or inconsistencies, and anyone considering Choi a reliable technical authority on ITF TaeKwonDo parameters really hasn't looked through this carefully.

It's evident that he copy and pastes parameters, then puts up illustrations in violation of them... Repeatedly...

Make up your own mind what that tells you about his knowledge.
 

Earl Weiss

Senior Master
Joined
Jan 27, 2009
Messages
3,581
Reaction score
923
It's not just that. He writes "toes of the stationary foot should point 45 degrees outward in the turning kick" , yet he uses a picture with an 180 degree pivot.

If you can't distinguish a 180 degree pivot with a 45 degree, you have no business writing a TKD textbook.

I wouldn't trust Choi about anything. He's the Donald Trump of TaeKwonDo. He just put his name on it as founder.
Your mistake again seems to be lack of sufficient information (unable to determine if you received the information and failed to understand or never received it) from a competent instructor. Every serious student of the system and using the texts knows the photos in the text are not always accurate. (keep in mind this was done before the age of digital photography) - there is even a disclaimer in the text - "The angle of the feet may appear out of position" but it only mentions stances that photos are not always accurate) Further - you have chosen the first photo but ignore 6 more showing the more appropriate angle.

Additionally serious students are aware that while General Choi his system just as body types vary so to will the standards on an individual basis.

As far as your trust in General Choi - no one cares.
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
Your mistake again seems to be lack of sufficient information from a competent instructor. Every serious student of the system and using the texts knows the photos in the text are not always accurate. (keep in mind this was done before the age of digital photography - there is even a disclaimer in the text - "The angle of the feet may appear out of position" but it only mentions stances that photos are not always accurate) Further - you have chosen the first photo but ignore 6 more showing the more appropriate angle.

As far as your trust in General Choi - no one cares.

Yes there are also pictures with the 45 degree base foot pivot. A blind chicken finds a piece of corn every now and then.

He just random picked turning kick photos, which is a bit inappropriate for a book about parameters.
 
OP
I

InfiniteLoop

Black Belt
Joined
Aug 30, 2021
Messages
523
Reaction score
107
Your mistake again seems to be lack of sufficient information (unable to determine if you received the information and failed to understand or never received it) from a competent inst
No mistake. Choi uses as his main picture a 180 degree pivot, instead of 45, cause he's clueless.
 
Last edited:

Latest Discussions

Top